Vitamin D plays a critical role in calcium metabolism and bone health in children and adults. It is now recognized that every tissue and cell in the body have a vitamin D receptor and thus every tissue and cell in the body is a target for vitamin D action. Studies suggest that increased exposure to sunlight and increased vitamin D intake reduces risk of many chronic diseases including autoimmune diseases, heart disease, infectious diseases, type II diabetes and cancer. Vitamin D deficiency and insufficiency is the most common nutritional deficiency and medical condition in children and adults throughout the United States. The major source of vitamin D for children and adults is exposure to sunlight. There is little vitamin D in the diet and thus to maintain a normal healthy vitamin D status requires taking a vitamin D supplement. Patients with malabsorption and children and adults who are infirm and unable to be exposed to any sunlight are at particularly high risk for vitamin D deficiency and its health consequences. Artificial ultraviolet irradiation is also a good source of vitamin D. KBD Inc. is a small business that makes the Sperti vitamin D producing lamp that has been in existence for more than 50 years and marketed for producing vitamin D. The lamp has been modified so that most of the spectral output is in the UVB region thus maximally producing vitamin D. The goal of this grant is to take this newly designed lamp and test its effectiveness in producing vitamin D in patients with inflammatory bowel disease who have been demonstrated to malabsorb vitamin D. Adult IBD patients with skin types 2,3,4 and 5 will be exposed to suberythemal dose of UVB radiation from the Sperti fluorescent lamp three times a week for three months. Blood levels of 25-hydroxyvitamin D, a measure of vitamin D status, will be the primary outcome for the study. Results from this study should provide efficacy data to support the commercial development of this novel vitamin D producing fluorescent lamp not only for patients with malabsorption syndromes but also elderly in nursing homes and for children and adults who cannot be exposed to sunlight and have a difficult time taking a vitamin D supplement. PUBLIC HEALTH RELEVANCE: The goal of this grant is to obtain data that exposure to a novel Sperti fluorescent vitamin D producing lamp is effective in improving the vitamin D status of patients with inflammatory bowel disease who have documented vitamin D malabsorption. It is anticipated that results from this grant will provide the impetus for the small business KBD Inc. to market and sell its product to patients who suffer from the intestinal malabsorption syndromes and who are vitamin D deficient.